National Taiwan Normal University

Xin-Ji Lai

Chau-Jern Cheng

Yu-Chih Lin

Chin-Yu Liu

A method for defect inspection of a transparent substrate comprises (a) providing an optical system for performing a diffraction process of object wave passing through a transparent substrate, (b) interfering and wavefront recording for the diffracted object wave and a reference wave to reconstruct the defect complex images (including amplitude and phase) of the transparent substrate, (c) characteristics analyzing, features classifying and sieving for the defect complex images of the transparent substrate, and (d) creating defect complex images database based-on the defect complex images for comparison and detection of the defect complex images of the transparent substrate.

Method for defect inspection of transparent substrate by integrating interference and wavefront recording to reconstruct defect complex images information

A method of structured illumination digital holography includes: (a) providing a structured illumination generating unit and binarization random number encoding unit to generate a coded structured illumination pattern; (b) sampling at least two patterns with phase shift which synthesized as a single structured illumination pattern to be encoded; (c) forming a single digital hologram, and wavefront reconstructing the single digital hologram; (d) performing a compressive sensing approach to recover the object wave with at least two phase shift patterns; and (e) reconstructing the separation of overlap spectrum, to obtain an image covering bandpass spectrum with different high frequency and low frequency.

Imaging method of structured illumination digital holography

An image processing method for processing a plurality of holograms includes the steps of: performing a Fourier transform operation on the holograms to result in a plurality of corresponding spectra in a spectrum space; calculating a sum of the plurality of spectra to obtain the synthetic spectrum; multiplying the synthetic spectrum by a weight function associated with the spectrum space to obtain a normalized synthetic spectrum, each function value of the weight function corresponding to a respective position in the spectrum space and being associated with distribution of the plurality of spectra in the spectrum space; and performing the inverse Fourier transform operation on the normalized synthetic spectrum to result in a normalized synthetic hologram.

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Taipei, Taiwan

Xin-Ji Lai